A known type of router, sold by The Black & Decker Corporation under part number KW800, is shown in FIG. 1. The router 2 has a motor housing 4 containing a motor (not shown) for driving a collet 6 to which a cutting or milling tool (not shown) is mounted to engage a workpiece (not shown) through an aperture 8 in a base 10. The motor housing 4 is mounted to a support member 12, and a pair of handles 14, 16 are integrally formed with the support member 12. The handles 14, 16 are mounted to respective inclined portions 14a, 16a, which extend from respective vertical portions 14b, 16b. The support member 12 has front and rear portions between which the motor housing is fixed in position by clamping the lower part of the motor housing 4 between the front and rear portions of the support member 12.
The support member 12 is slidably mounted relative to the base 10 by means of support columns 18, 20 which pass through the support member 12 and through respective vertical portions 14b, 16b, and is urged upwardly by respective compression springs 22, 24. The minimum separation of the support member 12 and base 10 is set by means of an upper abutment member 26 slidably mounted through an aperture in the support member 12 and fixable in position by means of a thumb screw 28. The abutment member 26 co-operates with a platform 30 which is rotatable relative to the base 10 and on which three lower abutment members 32, 34, 36 of different lengths are mounted, so that any one of the lower abutments members 32, 24, 36 can come into contact with the upper abutment member 26 when the support member 12 is moved downwards towards the base 10. The minimum separation between the support member 12 and base 10 (and therefore the depth of cutting of the cutting tool in the workpiece) is set by suitable choice of the axial position of the upper abutment member 26 in the support member 12 and the rotational position of the platform 30 on the base 10 to set the separation of support member 12 and base 10 at which the upper abutment member 26 comes into contact with one of the lower abutment members 32, 34, 36.
The router shown in FIG. 1 suffers from a number of drawbacks. For example, because the motor housing 4 is clamped between the front and rear portions of the support member 12 at its lower part, the motor housing 4 engages a relatively shallow recess in the support member 12 and it is therefore possible to misalign the motor housing 4 with the support member 12. This can result in the cutting tool mounted to the collet 6 not being arranged vertically. Also vibration of the motor in the motor housing 4 can cause lateral oscillation of the cutting tool. In addition, because the support columns 18, 20 pass through relatively short vertical portions 14b, 16b respectively, some angular movement of the motor housing 4 relative to the base 10 is possible as a result of manufacturing tolerances between the internal diameter of vertical portions 14b, 16b and support columns 18, 20. All of these factors can have a detrimental effect on the accuracy with which the cutting tool can cut.